1. Field of the Invention
The present invention generally relates to a cable assembly, and particularly to a cable assembly having a plurality of circuit boards for high speed signal transmission.
2. Description of Related Arts
With the development of communication and computer technology, high density electrical connectors are desired to construct a plurality of signal transmitting paths between two electronic devices. Each of these electrical connectors provides a plurality of circuit boards to thereby achieve improved signal transmission of different electrical characteristics through the connector. Such high density electrical connectors, such as cable assemblies, are widely used in internal connecting systems of severs, routers and the like requiring high speed data processing and communication.
U.S. Pat. No. 6,217,364, issued to Miskin et al., discloses a cable assembly including an insulating housing formed by a pair of substantially identical housing halves and an electrical cable with a plurality of wires terminated to conductive terminals overmolded in a plurality of thin flat wafers. The housing halves combine to define an interior cavity having a front opening and a rear opening. The wafers are closely juxtaposed in a parallel array and are positioned within the interior cavity of one of the housing halves such that the cable projects out of the rear opening of the cavity. The other housing half is then to completely enclose the cable and wafer subassembly. However, the cable and wafer subassembly are retained in the housing by securing the housing halves together through bolts and nuts, thereby complicating the assemblage of the cable assembly. Furthermore, an engagement of the housing halves is easy to become loose due to vibration during the transportation and other matters, whereby the cable and the wafer subassembly cannot be stably retained in the housing. Thus, an electrical connection is adversely affected between the cable assembly and a complementary connector.
U.S. Pat. No. 5,924,899 (the ""899 patent) and U.S. Pat. No. 6,102,747 (the ""747 patent), both issued to Paagman, each disclose a cable assembly. Referring to FIGS. 4a-4c and 5a-5c of the ""899/""747 patent, the cable assembly includes an insulating housing with a plurality of parallel slots defined therein and a plurality of modules received in the slots of the housing. Each module includes a circuit substrate, a receptacle carrier having a plurality of fork contacts at one end of the substrate and an insulation displacement contact (IDC) carrier at the other end of the substrate opposite the terminal carrier. The insulation displacement carrier has insulation displacement contacts connecting with conductors of corresponding cables. The modules each are retained in the housing through an interference fit with the housing. When the cable assembly is required to disengage from a complementary connector, a pulling force is exerted on an exposed end of the cable for releasing the engagement between the cable assembly and the complementary connector. However, the modules may be pulled back with regard to the housing, thereby adversely affecting an electrical engagement when the cable assembly mates with the complementary connector again. Furthermore, an additional device is employed to bond the cables together, thereby increasing the cost of the production.
U.S. Pat. No. 5,421,746, filed on Sep. 13, 1993 and issued to David, discloses a modular connector having a plurality of overmolded connectors encased in an outer shell. Each overmolded connector includes a circuit board overmolded in a casing. The circuit board provides an interface between electrical wires and contact surfaces. In order to ascertain a predetermined position and orientation of electrical connections in the modular connector, a plurality of keys are disposed in the modular connector. Obviously, the employments of the keys complex the manufacturing and the assembling of the product, and unavoidably increase the cost of the production.
Hence, an improved cable assembly is highly desired to overcome the disadvantages of the related arts.
Accordingly, it is an object of the present invention to provide a cable assembly having a plurality of circuit boards reliably retained in a housing thereof.
It is another object of the present invention to provide a cable assembly having overmolded means for substantially resisting a pulling force exerted on a cable thereof to thereby maintain a reliable electrical connection between the cable and a corresponding circuit board thereof.
It is still another object of the present invention to provide a cable assembly having a grounding plate for reducing crosstalk between adjacent cables thereof.
In order to achieve the above-mentioned objects, a cable assembly in accordance with the present invention for engaging a complementary connector, comprises an insulating housing, a plurality of circuit modules received in the housing, and a two-piece cover cooperating with the housing for retaining the circuit modules. Each circuit module includes a circuit board accommodated in the housing, a number of cables mechanically and electrically connecting with the circuit board, and an overmolded casing encasing therein a rear edge portion of the circuit board and front portions of the cables. The overmolded casing comprises a plurality of protrusions protruded from opposite faces thereof and a plurality of recesses defined on opposite faces for receiving corresponding protrusions on the overmolded casing of an adjacent circuit module.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings.